commit 9295c41d77 upstream.
Due to the way CUBC register is updated, a double flush is needed to
compute an accurate residue. First flush aim is to get data from the DMA
FIFO and second one ensures that we won't report data which are not in
memory.
Signed-off-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Fixes: e1f7c9eee7 ("dmaengine: at_xdmac: creation of the atmel
eXtended DMA Controller driver")
Reviewed-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>